The subject disclosure relates to the printing arts, the image processing arts, the color processing arts, spot color printing, and the like.
A spot color is generally a color used in printing that differs from a process color. The standard process colors, cyan, magenta, yellow, and black (CMYK) are typically combined as needed to create the colors of an output document. In some instances, a particular color, which would normally be created by combining CMYK, is added to a printer as a fifth (or sixth) colorant, avoiding wasteful combination of CMYK inks. For example, a company may have a special color as part of its logo. To keep costs down in printing literature, the company may employ a five or six color printer, with the special color of the logo included as a single colorant. A spot colorant is intended to be used alone and to represent a particular end color, whereas the standard CMYK colors are intended to be combined to form an end color. In a typical six-color offset printing press, the press would include four process colors and two spot colors to hit specific important colors like a company logo, or the like. In digital printing, spot colors (colors that would have been printed using a single ink) are emulated using a spot color recipe.
For emulating spot colors on a modern digital press that supports additional spot colorant(s) besides the traditional colorants, i.e. CMYK (Cyan, Magenta, Yellow, and Black), a common solution is for DFE (Digital Front End) to let user control if the spot colors will be rendered in CMYK or CMYK plus the additional colorant. This control can be set for the entire spot color library, or for each spot color. However, setting this attribute for each spot color can be tedious and error-prone. When the target device changes, e.g. a destination update, or a different output colorant set is selected, the recipes will change and the previous determined attributes will become out-of-date.
Continuing with the digital printing example, when four color printing (e.g., CMYK) is augmented with one or more extended gamut colorants, it is the common case that users of such digital printing either do not know what spot color “benefits” from the loaded, in use, extended gamut, OR, the users must laboriously manually select a spot color that is known to benefit. Additionally, it is common that users are unable to assess the job for the optimal extended gamut colorant if it is not loaded.
On DFEs, Spot Colors are rendered with the special recipes defined by the system. Users occasionally might want to change the system defined recipes, by a means such as a Spot Color Editor, which in general is a DFE UI feature. When the job is sent, if the spot colors called out in the job are modified in the spot color editor, the user defined recipes will be used. However, there are usually thousands of spot colors that are supported on the system. It is hard for a user to scroll down the list, skip those unrelated colors, and find the spot colors that he or she wants to modify. Some filtering mechanism would help, but that still takes some effort for the user to perform the filtering.
Currently DFEs enable the setting of one color mode (e.g., CMYK) with one destination profile on a job/queue/page exception. For extended gamut printing systems (e.g., Edmonton), users do not want to apply all 5 colorants to all objects on a page/job. The reasons could be image quality or cost considerations.
What is needed is a system that enables users to specify the colorants and associated destination profile for each object type within an extended gamut mode rendered page. Furthermore, the user needs to be able to control the colorants and associated destination profile for each individual spot name.